This invention relates in general to certain new and useful improvements for automatically de-energizing power utilizing equipment after a lack of animal activity for a predetermined time period, and more particularly, to an apparatus and method capable of de-energizing electrically operable equipment if animal activity has not generated energy in a certain spectral wavelength in a particular environment within predetermined time period and thereafter permitting energization of such equipment if animal activity is so detected.
As a result of fossil fuel shortage, strong opposition to nuclear generated electrical power, and economic unavailability of other forms of power, e.g. geothermal power and the like, there has been a strong need for energy saving devices. Further, as a result of recent energy shortage conditions, there has also been a number of relatively recently proposed energy savings devices. Many of these devices are not highly effective. Other types of energy savings devices while they may be effective, are oftentimes complex, difficult to effectively operate and are not economically feasible.
There have been several prior art detection systems designed to detect human activity in a specified environment as for example, a room or other enclosure. One such prior art device utilized a source of microwave radiation. Thus, if there was human activity within the specified environment the microwave radiation would cause a triggering of a signal to energize or de-energize electrically operable equipment.
There have been other forms of human detection systems to detect human activity, as for example, passing through a doorway or across some barrier or threshold. One such detection system used a light beam and light sensor such that breaking of the beam would cause initiation of an electrical signal. Thus, the passage of a person through a doorway would initiate an electrical signal to operate some electrically operable equipment, e.g. would trigger an alarm or otherwise cause the door open.
The prior art is replete with a number of burglar alarm systems, burglar deterrent timing circuits, and the like. Exemplary of such circuits are the Stettner et al. U.S. Pat. No. 3,761,912 in which a timing circuit is used in connection with a silicon controlled rectifier for generating an alarm or energizing lights for a selected period of time in response to the occurrence of a sound. However, after a substantial period of time, the circuit is de-energized and turns off the lights and/or sound. However, in accordance with conventional burglar alarm systems or other intrusion devices, the alarm would be generated almost immediately after detection of the sound.
U.S. Pat. No. 4,012,732 to Herrick also discloses a security device in which an alarm is actuated after a predetermined time period of no physical activity. The circuit utilizes a means to sense an inanimate object as well as an animate object and relies upon a clocking system to actuate an alarm after a predetermined period of inactivity.
The White et al. Pat. No. 3,445,836 also discloses an alarm system which operates by means of audio frequency signals and includes a plurality of sound actuated sensors. The circuit includes various amplifiers and pre-amplifiers in order to generate an alarm in response to an ambient noise condition. The Kedjierski et al. U.S. Pat. No. 4,099,168 similarly discloses an intrusion alarm system which operates on the basis of an audio frequency signal.
Heretofore, there has not been any known effective system for electrically de-energizing electrically operable equipment when a lack of animal activity, such as human activity, is detected or sensed for a predetermined time period, and preferably a user adjustable time period, and in a specified environment.
There has been at least one proposed system using ultrasonic radiation in a specified environment for sensing the presence of or a lack of human activity. In this case, the ultrasonic radiation was generated as a type of standing wave such that if the wave was not disturbed, then equipment could be automatically de-energized. Any disturbance in the standing wave would cause a re-energization of the equipment. A similar system has been proposed used with a standing wave of microwave radiation. This latter proposed system also would operate in a similar manner.
Each of the aforementioned proposed systems were not passive in that it was necessary to generate a standing wave or at least a type of standing wave in order to detect the presence or lack of presence of animal activity. Moreover, by their very nature, these systems were sensitive in that even a small insect could disturb the standing wave thereby causing an undesirable triggering of the system.